There are provided a first insulator substrate; a first contact comprising a plurality of contact pins arranged in an array on a top surface of the first insulator substrate; a second insulator substrate; a second contact comprising a plurality of contact pins arranged in an array on an undersurface of the second insulator substrate; a metal plate sandwiched between an undersurface of the first insulator substrate and a top surface of the second insulator substrate; and a metal shell accommodating the first and second insulator substrates, the first and second contacts and the metal plate; wherein the metal plate comprises a pair of protruding parts formed on both ends in an array direction of the contact pins, being oriented toward the outside; and the metal shell comprises a pair of windows to be engaged with the pair of protruding part.